Safety device for cranes.



D. D. LEWIS.

SAFETY DEVICE FOR CRANES.

(Application filed Jan. 16, 1900.)

(No Model.)

Patented May 22, I900.

Shee tsSheet Kim IIIVEIITOR ar ag-1% Qmw No. 650,|30. Patented May 22, I900.

D. D. LEWIS.

SAFETY DEVICE FOR G'RANES.

. (Application filed Jan. 18, 1900,) (No Model.) 2 Sheets-Sheet Z.

P V y G WITNESSES I INVEN T0]? 3M3 Arron/m.

UNITED STATES DAVID 1). LEWIS, or

PATENT FFICE.

LORAIN, ouIo.

SAFETY DEVICE FOR CRANES SPECIFICATION forming part of Letters Patent No. 650,130, dated May 22, 1900. Application filed January 16, 1900. Serial No. 1,627. No model.)

Tn 117/ '//'71 out it 71141.7 (IHHYIIII 130 it known that I, DAVID D. LEWIS, of L- rain, in the county of Lorain and State of Ohio,

,tiee for handling the ladies w iich receive the lower ends.

molten metal from the converters and carry it to the ingot-molds. Itis, however, useful iii/connection with vertically moving and swinging cranes generally.

The object of the invention is to provide means which will in case of breakage or derangement ol the hydraulic or other craneoperating mechanism operate automatically to catch the crane-arm, and thereby prevent accident.

\Vith this object in view my invention consists in the combination,witha erane-postpnd movable crane-arm, of cooperatin g safety devices carried by said post and adapted upon the descent of said arm to engage each other, and thereby support the arm and itsload; also, in the provision of means whereby in the normal operation of the crane such engagement may be prevented and the cranearin be lowered without obstruction.

The invention also consists in the novel construction and combination of parts, all as hereinafter described, and pointed out in the appended claims, reference being had to the accompanying drawings, in which- Figure 1 is a side view of a ladle-crane embodying my invention; Fig. 2, a front view of a portion-of the same on a larger scale; Fig. 3, a detail view of one of the safety-links detached, and Fig. 4 a detail view showing in side elevation the arrangement of guide-pulleys for theoperating-chain.

The letter A designates the vertical cranepost, which turns in bearings atits upper and B' is the bifurcated horizontal crane-arm, which embraces the post A and ,moves up and down on guides thereon by the action of ahydraulic cylinder 0. D is a ladle supported on trunnions on said arm.

These struction and need not be further described.

Secu red to each lateral member of the cranearm are brackets f, in which are journaled short rocker-shafts F, running parallel with the crane-arm. Fastened to each of said shafts is a pair of upwardly-extending links G, connected at their upper ends by a pin g. At the opposite end portion of said shaft is an arm G, which extends transversely over toward the other shaf t. Connected to the inner ends of the two arms G are short chains II, which are connected to each other and also to the lower end of a chain or cable II. The chain II extends upwardly to a point near the top 'of the crane-post A, thence horizontally over guide-pulleys K, K, and K and thence down within reach of the eraue-operatofis plat form, its lowerend extending below said platform and provided with counterweights L.

The guide-pulley K is hung from an arm 7s,con-

nected to the post A. The pulley K is journaled in a bracket M, swiveledto a depending support M, (see Fig. 4,) said bracket being engaged by a horizontally-extending rod M secured to the arm 7.;. The guide-pulley K is journaled in a bracket M which is swiveled to a suitable overhead support M. It will be readily seen that the three guide-pulleys, being supported in the manner described, will follow the swinging movement of the crane-arm to maintain the same relation thereto in all positions of the said arm. P P designate the hook-plates, one of which' is firmly secured to each side of the cranepost A. On each of these plates is a hook projection 2, led up to by acurved surface 1). These hooks are sov placed that when the crane-arm is at its highest elevation the pins g of the links G will be slightly above the books, but in position to engage the same should the crane-arm fall. (See the full-line position, Fig. 2.) In this position should any aecidentoceur to the hydraulic or other craneoperating mechanism of a character to let the crane-arm fallthe link pins 9 will at once engage the hooks, and thus support said arm with its load. In the normal operation of lowering the crane-arm it is necessary for the operator to pull on the chain II, which rocks the. shafts l and throws the links G useful in other connections than that shown self to its use in this connection; nor do I a vertically-movablecrane-arm, of cooperatthereby support the latter, together with.

means for moving said link to normally prevent such engagement.

5. The combination with a 1: ranc-post, and a vertically-1novablo crane-arm, of swinging links on said arm, two hooks secured to said post and arranged to beongagcd by the re spective links, and means common to both links for moving them out of position'fto engage the said hooks.

6. The combination with a cranepost having hooks secured thereto, and curved, surfaces leading up to the said hooks, of swinging links arranged, as the crane-arm rises, to ride up said. curved surfaces into" position to engage said hooks upon the descent of said arm, and means for swinging thelinks away from the post to prevent such engagement.

7 The combination with a crane-post having hooks secured to opposite sides thereof, a vertically-movable crane-arm having swinging links pivoted thereto and arranged to engage the respective hooks, arms connected tothe pivots of said links, and mcansconnected to'the said arms fol-swinging thc'said links, substantially as described.

8. In a safety device for cranes, the combination withtherotary crane-post, the vertically-movable crane-arm supported by said post, and. the swinging safety-links pivoted to the crane-arm and arranged to engage hooks on the-said post, of the armsconnectqd to the pivots of the said links, the counterweighted chain or cable,-connected to said arms, and the swivelcd guide-pulleys for said 7 5 chain or cable.

In testimony whereof I have affixed my signature in presence of two witnesses.

' DAVID D. IJEWl H.

suflicientLv away from the post A to clear the hooks p in their descent.

It will be readily seen that the device is and described where cranes-of this type are employed. Hence I do not wish to limit my- Wish to limit myself to the details of ,construction and arrangement which I have herein shown and-described, as these may be varied without departing from the spirit and scope of my invention as set forth in'the appended claims. 9

Having thus described my invention,'what I claim, and desire to protect by Letters Patent, is

1. The combination with a crane-'post, and

ing safety devices carried by said arm and 60 post, in posltlon to automatically engageeach other upon thedescent of the said arm and means for normally preventing suchengagement. a

2. The combination with a crane-post,-and a vertically-movable crane-arm, hooks secured to said posts, and links adapted to engage the said hooks and support said arm, in, elevated position, together with means for preventing such engagement in the normal operation of the crane.

3. The combination with a crane-post and e a vertically-movable crane-arm, of aswinging link'on said arm arranged toautomatically engage said post to support said arm, and meansfor preventing such engagement in the normal operation of the crane.

4. The-combination with a. crane-post, and a vertically-movable crane-arm, of a swinging link on said arm, a hook on the eranepostarranged to be engaged by the said link, and

Witnessesz. I

II. M. DAVIES, D. W. Lnwnnsca. 

